Apparatus of a light filter for electric lamps



Dec. 8, 1936. i A. BRAUNE 2,

APPARATUS OF A L IGHT FILTER FOR ELECTRIC LAMPS Filed April 27, 1934 atented Dec. 8, 1936 PATENT OFFICE APPARATUS or A LIGHT m'rnn r ELECTRIC mms Albert Braune, Artern,

Application April 27, 1935!, Serial No. 722,802 In Germany April 6, 1933 4 Claim.

This invention relates to light filters and has special reference to a light filter for use in connection with incandescent lamps. v

One important object of the invention is to a provide an improved device of this character adapted to be applied to an incandescent lamp and having a bowl shaped vessel containing a suitable liquid, a similar but smaller vessel having a vacuum chamber being nested within the 1p first container.

A second important object of the invention is to provide a device of this character, wherein the two bowl shaped members are separated by an air space,

to provide a novel device of this character having improved means for securing the device directly to the globe of an incandescent lamp.

A fourth important object of the invention is to provide an improved device of this character,

vwherein suspension means for the bowls are attaehed to the bowls themselves.

With the foregoing and other objects in view, the invention consists in the details of construction, and in the arrangement and combination of parts to be hereinafter more fully set forth and claimed.

In the drawing: Figure 1- illustrates one embodiment of the light filter and Figure 2 illustrates a modification thereof.

In the embodiment of the invention as herein disclosed there is provided a double walled body or bowl a, forming a container which is substanfl tially filled with a liquid b. This liquid is prefer ably a brine such as sea water and may be colored with a suitable substance to provide a desired color of light, for advertising, ornament, physical properties, protection of the eyes, or treatment of diseases. This outer bowl is filled through a suitable opening closed by a plug 0. Within this outer bowl is nested a double walled vessel or bowl d, the space between the two walls being evacuated to provide a vacuum space e. These two bowls are separated by an air space 1, the edges of the bowls are screwed or otherwise se cured together as indicated at h, and air holes g are provided to permit circulation of air in the air space. The vacuum space being interposed between the lamp and the liquid prevents overheating of the latter.

The upper, edge of the inner bowl is internally threaded andin this threaded portion may be screwed a ring i having a cushioning pad I extending around its inner face and engaging the A third important object of the invention is.

lamp n somewhat above its greatest diameter. The ring 2 is vented as at q.

In another form of means for mounting the device on the lamp there is provided a ring it which extends upwardly and then inwardly to the shoulder 0 of the bulb where it is provided with a downturned flange lc' carrying a cushion m. The inwardly extending part of the ring it is vented as at r. The pad m engages the shoulder 0 just \below the threaded base 1) by means of which the lamp is screwed into a suitable socket.

Chains w have their lower ends attached to the bowl a and their upper ends suitably attached to relatively fixed means (not shown) for suspending the bowls.

The curvature of the bowls is preferably on a greater radius than the curvature of the lower part of the lamp bulb so that these bowls may be said to be somewhat flatter than the lamp bulb.

By means of this invention there is produced a lighting effect of high efficiency, the light passing through the invention being of great softness and yet not losing its illuminating power to any appreciable extent. Moreover, the vacuum layer prevents undue heating of the liquid in the outer globe and also eliminates heating of an illuminat-' ed object even when the device is brought close thereto.

There has thus been provided a simple and eflicient device of the kind described and' for of nested vessels shaped to surround the end ofan incandescent lamp opposite its base, each of said vessels having spaced inner and outer walls to provide a chamber, the chamber in the inner vessel being evacuated to form a vacuum chamber and thechamber in the outer vessel being filled with transparent fluid.

2. In a device of the kind described, a plurality of nested vessels shaped to surround the end of an incandescent lamp'opposite its base, each of said vessels having spaced inner and outer walls I,

to provide a chamber, the chamber in the inner vessel being evacuated to form a vacuum chamber and the chamber in the outer vessel being filled with transparentfiuid, said vessels being spaced to provide an air chamber between the vessels.

3. In a device of the kind described, a plurality of nested vessels shaped to surround the end of an incandescent lamp opposite its base, each of said vessels having spaced inner and outer walls to provide a chamber, the chamber in the inner vessel being evacuated to form a vacuum chamber and the chamber in the outer vessel being filled with transparent fluid, said vessels being of bowllike form, and a supporting ring at the mouth of the inner vessel adapted to engage a lamp between its base and its greatest diameter.

4. In a device 01 the kind described, a plurality of nested vessels shaped to surround the end of an incandescent lamp opposite its base, each of said vessels having spaced inner and outer walls to provide a chamber, the chamber in the inner vessel being evacuated to form a vacuum chamber and the chamber in the outer vessel being filled with transparent liquid, said vessels being spaced to provide an air chamber between the vessels, said vessels being of bowl-like form, and a supporting ring at the mouth of the inner vessel adapted to engage a lamp between its base and its greatest diameter.

ALBERT BRAUNE. 

